Stopping power of low-velocity ions in solids: inhomogeneous electron gas model

Abstract

A self-consistent model for the calculation of electron scattering and stopping coefficients of slow ions in a non-homogeneous electron gas is developed. The model permits to account for realistic electron density profiles in the evaluation of the average energy loss of slow ions in solids. The screening parameter in the potential and the scattering phase shifts are calculated in a non-perturbative way, as a function of the local electron-gas density. We show that the inhomogeneity effect can modify the Z 1 dependence of the low-velocity stopping powers. The differences between previous calculations and experimental stopping-power data, for channeled and random incidence trajectories of ions in solids, are well explained by this approach.